Undergraduate Research Programhttp://udspace.udel.edu/handle/19716/4234
Thu, 24 May 2018 19:52:24 GMT2018-05-24T19:52:24ZThe Diversity and Abundance Of Natural Enemies: Parasitic Wasps in Urban Deciduous Forest Fragmentshttp://udspace.udel.edu/handle/19716/23067
The Diversity and Abundance Of Natural Enemies: Parasitic Wasps in Urban Deciduous Forest Fragments
Ference, Cassandra
This study evaluated the diversity and abundance of this important group of bio-control agents in Northern Delaware forest fragments. Parasitic wasps from six forest fragments surrounded by different types of land use were sampled using bowl traps. Collected wasps were identified down to family. The diversity was measured using Simpson’s Diversity Index. An Analysis of Variance was run to see if surrounding land use had any impact on the diversity or abundance.
I found that there was an intermediate level of parasitoid diversity over all. The six most abundant families found were Ichneumonidae, Braconidae, Diapriidae, Pompilidae, Tiphiidae, and Platygastridae. Furthermore, the surrounding land use did not have an impact on the diversity and abundance. More field seasons need to be conducted and more taxonomic resolution is necessary in order to determine the diversity and abundance of parasitic wasps in Northern Delaware forest fragments.
Thu, 01 Mar 2018 00:00:00 GMThttp://udspace.udel.edu/handle/19716/230672018-03-01T00:00:00ZMathematical Models for Evaporation of Thin Filmshttp://udspace.udel.edu/handle/19716/22922
Mathematical Models for Evaporation of Thin Films
Rathee, Vikramjit
Evaporation is a major cause of thinning of tear film which can eventually cause damage to ocular surface. The aim of the presented research was to analyze some of the many facets of evaporation of the aqueous layer of the tear film through development of mathematical models. In chapter 2, using the assumption of negligible film thickness, no fluid motion and a flat air/film interface, the diffusion equation for the water vapor concentration was solved numerically on a fixed domain and solutions were analyzed. Theoretical steady state predictions were also matched with solution profiles obtained from numerical simulation. Later, in chapter 3, film thickness was not overlooked and decrease in film thickness due to evaporation changed the domain for the vapor diffusion with time. The partial differential equations describing the diffusion of water vapors were then solved numerically on this moving domain by introducing a new independent variable which mapped the moving domain into fixed domain. Comparison between solution for the fixed boundary and moving boundary problems revealed that the use negligible thickness assumption did not represent the behavior of the system as accurately as expected. Lastly, in chapter 4, a lubrication model was derived using a thin film approximation which related film thickness, evaporation rate and fluid motion. Further, expression for evaporation rate was developed for the deformed thin film where vapor diffusion outside the film limited the evaporation of liquid molecules. We hope to adapt this model of thin film dynamics to more complex tear film models in future research.
Wed, 01 May 2013 00:00:00 GMThttp://udspace.udel.edu/handle/19716/229222013-05-01T00:00:00ZArrests at the Midnight Hour:Public Perceptions of the Secret Police in Germany and Russiahttp://udspace.udel.edu/handle/19716/21832
Arrests at the Midnight Hour:Public Perceptions of the Secret Police in Germany and Russia
Plyasunova, Anastasia
East Germany and Russia both made use of a secret police/political police force in the twentieth century; both are also former communist states and European countries. But the public in those two countries perceived the secret police very differently. In East Germany, the Ministerium für Staatssicherheit (the Stasi) were hated, while in Russia, the KGB (Committee for Government Safety) was tolerated, with its thrice-elected president being a former agent himself. Post-Communism, unified Germany chose to release the files that the Stasi had kept, allowing people to read them, a luxury that Russians have not yet had. Finally, in Russia alone was the political police reorganized and reappropriated by the government, as the FSB. This thesis looks at each of those three points separately, and derives three conclusions.
Fri, 01 Dec 2017 00:00:00 GMThttp://udspace.udel.edu/handle/19716/218322017-12-01T00:00:00ZDemand Response Programs Focusing upon SCE and ERCOThttp://udspace.udel.edu/handle/19716/21665
Demand Response Programs Focusing upon SCE and ERCOT
Styer, Andy
This paper examines the current literature of demand side management, focusing on the demand demand response aspects, before providing a comparative case study of current demand response programs in Southern California Edison and the Electric Reliability Council of Texas. The electrical grid faces severe challenges and both Texas and California have turned to demand response as a potential solution. Despite the two state’s regulatory philosophy differences their demand response programs represent two sides of the same demand response coin. Both states need the benefits of demand response for the stability of their grids and doubtless will rely on them more and more heavily moving forward.
Mon, 01 May 2017 00:00:00 GMThttp://udspace.udel.edu/handle/19716/216652017-05-01T00:00:00Z